mhash_keygen_s2k
(PHP 4 >= 4.0.4)
mhash_keygen_s2k -- Generates a key
Description
string mhash_keygen_s2k ( int hash, string password, string
salt, int bytes)
mhash_keygen_s2k() generates a key that is bytes long, from
a user given password. This is the Salted S2K algorithm
as specified in the OpenPGP document (RFC 2440). That algorithm
will use the specified hash algorithm to create the key.
The salt must be different and random enough for every key
you generate in order to create different keys. That salt
must be known when you check the keys, thus it is a good
idea to append the key to it. Salt has a fixed length of
8 bytes and will be padded with zeros if you supply less
bytes.
Keep in mind that user supplied passwords are not really
suitable to be used as keys in cryptographic algorithms,
since users normally choose keys they can write on keyboard.
These passwords use only 6 to 7 bits per character (or less).
It is highly recommended to use some kind of transformation
(like this function) to the user supplied key.
mhash
(PHP 3>= 3.0.9, PHP 4 )
mhash -- Compute hash
Description
string mhash ( int hash, string data [, string key])
mhash() applies a hash function specified by hash to the
data and returns the resulting hash (also called digest).
If the key is specified it will return the resulting HMAC.
HMAC is keyed hashing for message authentication, or simply
a message digest that depends on the specified key. Not
all algorithms supported in mhash can be used in HMAC mode.
In case of an error returns FALSE.
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